软胶结模型参数对黄土应力-应变特性的影响

Influence of Parameters of Soft Cementation Model on Stress-Strain Characteristics of Loess

采用颗粒流方法开展三轴压缩的离散元分析,研究软胶结接触模型在模拟黄土时其细观参数对力学特性的影响;依次改变需考察的参数取值,分组进行三轴压缩。结果表明:在模拟低含水率、结构性强的软化型黄土时有较好契合度;摩擦系数、胶结强度对应力-应变曲线软化类型及偏应力峰值影响较大,法向与切向刚度比,胶结抗拉强度等不改变软化类型,只影响应力-应变曲线的变化幅度。摩擦系数,软化系数等对体应变的影响表现为系数越大,体应变的增速越快。

The particle flow method was used to carry out the discrete element analysis of triaxial compression,and the influence of micro parameters on mechanical properties of soft cemented contact model in loess simulation was studied. The values of the parameters to be investigated were changed successively, and triaxial compression was performed in groups. The results show that in the simulation of soft loess with low moisture content and strong structure, it has a good fit. The friction coefficient and bonding strength have great influence on the softening type and deviatoric stress peak of the stress-strain curve. The ratio of normal to tangential stiffness and bonding tensile strength do not change the softening type, but only affect the variation range of the stress-strain curve. The effect of friction coefficient and softening coefficient on volumetric strain is that the larger the coefficient, the faster the growth rate of the volumetric strain.